Which statement best describes how typical home-cooking (heating to ~70–100°C) and stomach conditions (low pH) together affect dietary proteins in terms of safety and digestibility?

Cooking heat denatures proteins and often kills pathogens, while gastric acidity further denatures proteins and activates proteases (like pepsin), together improving digestibility and reducing microbial risk.

High cooking temperatures cause immediate hydrolysis to free amino acids, so no further digestion is required in the stomach; low pH in the stomach only inhibits protease function.

Cooking heat typically strengthens tertiary structures making proteins resistant to digestion, and stomach acidity has no effect on protein conformation or protease activity.

Cooking at these temperatures converts dietary proteins into fats which the stomach then emulsifies, and gastric pH neutralizes proteins preserving their native function.